Hot air balloons were not available for private use in 1910s when the series is set.
The balloon shown in this episode is a hot air balloon, not a gas balloon, as suggested by Angela to Elizabeth. Hot air balloons stay aloft by heating the air in the envelope (balloon) and continually heating the air to stay aloft, only opening the envelope to release the hot air for landing. Gas balloons seal the gas into the envelope, thereby staying aloft until the gas is released for landing.
"Lucas" calls "Fiona" by her actual name, Kayla, instead of her character name while they are at the oil rig.